WO2022171641A1

WO2022171641A1 - Identifying interference in received echo signals from a group of sensors

Info

Publication number: WO2022171641A1
Application number: PCT/EP2022/053053
Authority: WO
Inventors: Jean Francois Bariant; Anto Joys YESUADIMAI MICHAEL
Original assignee: Valeo Schalter Und Sensoren Gmbh
Priority date: 2021-02-10
Filing date: 2022-02-09
Publication date: 2022-08-18
Also published as: CN116806318A; EP4291922A1; JP2024506087A; DE102021103058A1; KR20230146046A

Abstract

The invention relates to a method for operating a sensor arrangement (12) having a control unit (14) and a plurality of sensors (16) which are arranged in at least one group (18, 20), wherein the sensors (16) are connected to a common electrical supply, in particular via the control unit (14), comprising the steps of using the sensors (16) to emit sensor signals, wherein the sensors (16) in each group (18, 20) emit the sensor signals thereof in the particular group transmission phase thereof, receiving echo signals on the basis of reflections of the sensor signals, transmitting the received echo signals from the sensors (16) to the control unit (14), and identifying interference (38) in the received echo signals from the at least one group (18, 20) on the basis of a comparison of at least two of the received echo signals from the corresponding group (18, 20). The invention also relates to a corresponding sensor arrangement (12) for a vehicle (10) for operation according to the above method. The invention also relates to a driving assistance system for a vehicle (10) having a sensor arrangement (12) as described above.

Description

Identifying a disturbance in received echo signals from a group of sensors

The present invention relates to a method for operating a sensor arrangement with a control unit and a plurality of sensors which are arranged in at least one group, the sensors being connected to a common electrical supply, in particular via the control unit.

The present invention also relates to a method for operating a sensor arrangement with a control unit and a plurality of sensors which are arranged in at least two groups, the sensors being connected to a common electrical supply, in particular via the control unit.

The present invention also relates to a sensor arrangement for a vehicle with a control unit and a plurality of sensors which are arranged in at least one group, the sensors being connected to a common electrical supply, in particular via the control unit, and the sensor arrangement being able to be operated with carried out according to the above procedure.

In addition, the present invention relates to a sensor arrangement for a vehicle with a control unit and a plurality of sensors which are arranged in at least two groups, the sensors being connected to a common electrical supply, in particular via the control unit.

Furthermore, the present invention relates to a driving support system for a vehicle with a sensor arrangement as described above.

Sensors are increasingly being installed in current vehicles in order to monitor an environment around the vehicle. These sensors, also referred to below as environmental sensors, make environmental information available that can be used, for example, by various driving support systems of the vehicle. The driving assistance systems can support a driver of the relevant vehicle in the manner of a driver assistance system, or provide functions for implementing autonomous driving. In a sensor unit, the sensors are often connected to a common electrical supply. For this purpose, the sensors are connected to a control unit, for example via a supply line, which not only supplies the environmental sensors with electrical energy, but also receives and evaluates sensor information from the sensors in order to detect objects in the area that are dangerous for the vehicle and to generate appropriate warnings. The sensor information can include echo signals that are received as reflections of sensor signals sent out with the sensors. The echo signals contain, for example, a point in time of a first echo detected by the respective sensor on objects in the area. The echo is characterized in that a reception amplitude of the sensor is above a limit value. In addition to the time of the received echo, the echo signals can contain a duration of the received echo and/or a reception amplitude of the received echo. The echo signals can also contain a number of echoes from objects in the vicinity that are detected by the respective sensor. The above explanations regarding the received echo apply. No signal is generated for times when no echoes are received, for example when a received amplitude is below a limit value. In addition, the sensors can generate flow curves with the echo signals and transmit them to the control unit. The flow curves contain a history of the received amplitude over time and thus also contain amplitude values for intervals in which the received amplitude of the respective sensor is below the limit value, i.e. by definition no echo is received. In this case, the limit value can have a time profile, since, for example, reflections from nearby objects are received with a larger amplitude due to the propagation than reflections from objects that are more distant but are otherwise of the same type.

Because the sensors are supplied together, the sensors can be wired easily. In particular, due to the joint supply of the sensors via the control unit, the wiring can be established in accordance with a data connection that is also required from the control unit to the sensors. Correspondingly, a supply line can be laid parallel to the data line and thus preferably at the same time, or only one line is laid, which is used both as a supply line and as a data line. The sensors mentioned can be, for example, ultrasonic sensors or also radar sensors or others. These sensors emit sensor signals and receive echo signals based thereon, in which objects in the vicinity of the vehicle can be identified as echoes. Ultrasonic sensors thus emit ultrasonic pulses and receive ultrasonic echoes of the emitted ultrasonic pulses from the objects in the vicinity of the vehicle. In current vehicles, it is common for a first set of sensors to be located along a front of the vehicle and a second set of sensors to be located along a rear of the vehicle. Each group currently includes four to six individual sensors. These sensors are therefore both arranged in a close spatial relationship and also record a coherent part of the environment of the vehicle. An arrangement of ultrasonic sensors along the long sides of the vehicles is also becoming increasingly widespread, which for the reasons mentioned can also be connected to the control unit as independent groups.

In order to emit the ultrasonic pulses, the ultrasonic sensors require a particularly large amount of energy, with a large amount of electrical power having to be provided due to the essentially simultaneous emission of the ultrasonic pulses. In order to reduce the power required, the sensors of the various groups therefore send out their sensor signals in groups with a time offset to other groups. After the ultrasonic pulses have been emitted, the ultrasonic sensors receive the echo signals based on the reflections of the emitted sensor signals on objects in the vicinity of the vehicle. In order to be able to recognize the reflections of the sensor signals on the objects as echoes in the echo signals, an electrical signal amplification of the received echo signals is necessary since the amplitude of the received echo signals decreases sharply with increasing time after the transmission of the ultrasonic pulses.

Errors in the reception of the echo signals can occur due to disturbances in the supply of the ultrasonic sensors. These disturbances can lead to incorrect detection of objects in the area surrounding the vehicle, ie to incorrect detection of non-existent objects, as a result of which, for example, emergency braking systems can be incorrectly prompted to perform emergency braking. The disturbances can be caused by external influences or by the supply itself, for example in the control unit. Ripple currents can occur, in particular when the control unit has to provide high power, as is the case, for example, when the sensor signals are transmitted by the sensors in each group, with a supply voltage being provided being superimposed as DC voltage with AC voltage components.

The problem of the electrical supply can occur more frequently with current sensors or driving support systems, since the current sensors emit the sensor signals over a longer period of time than older sensors, in particular in the form of a plurality of individual signal pulses which together form the sensor signal. As a result, the sensors must be supplied with the required power over a longer period of time. In addition, the pulses lead to greater alternating components in the supply. In order to avoid occurring disturbances in the supply, in principle different circuitry solutions can be used, for example capacitors or also ripple filters. However, these are associated with great effort and corresponding costs.

Proceeding from the prior art mentioned above, the invention is therefore based on the object of specifying a method for operating a sensor arrangement with a plurality of sensors, as well as a corresponding sensor arrangement, which enable simple and cost-effective detection of the surroundings without interference.

The object is achieved according to the invention by the features of the independent claims. Advantageous refinements of the invention are specified in the dependent claims.

According to the invention, a method is thus specified for operating a sensor arrangement with a control unit and a plurality of sensors which are arranged in at least one group, the sensors being connected to a common electrical supply, in particular via the control unit, comprising the steps of emitting sensor signals with the Sensors, the sensors of each group sending out their sensor signals in their respective group transmission phase, receiving echo signals based on reflections of the sensor signals, transmitting the received echo signals from the sensors to the control unit, and identifying a disturbance in the received echo signals of the at least one group based on a comparison of at least two of the received echo signals from the corresponding group.

According to the invention, a method is also specified for operating a sensor arrangement with a control unit and a plurality of sensors which are arranged in at least two groups, the sensors being connected to a common electrical supply, in particular via the control unit, comprising the steps of emitting sensor signals with the Sensors, wherein the sensors of each group transmit their sensor signals in their respective group transmission phase, and the group transmission phases of the at least two groups have a time offset, receiving echo signals based on reflections of the sensor signals, transmitting the received echo signals from the sensors to the control unit, and identifying one Interference in the received echo signals of each group based on the time offset of the group transmission phase and a duration of the group transmission phase of at least one other group.

According to the invention, a sensor arrangement for a vehicle is also specified with a control unit and a plurality of sensors which are arranged in at least one group, the sensors being connected to a common electrical supply, in particular via the control unit, and the sensor arrangement being able to be operated with the above procedure is performed.

According to the invention, a sensor arrangement for a vehicle is also specified with a control unit and a plurality of sensors which are arranged in at least two groups, the sensors being connected to a common electrical supply, in particular via the control unit, and the sensor arrangement for operation according to above procedure is performed.

Furthermore, according to the invention, a driving support system for a vehicle with one of the above sensor arrangements is specified.

The basic idea of the present invention is therefore to be able to identify disturbances in the received echo signals, which are caused by errors in the common supply, and thus to be able to handle them accordingly. Especially if the electrical supply, for example via the control unit, has to take place with high power, as is the case, for example, when the sensor signals are transmitted by the sensors of the at least one group, so-called ripple currents can occur, in which case a DC voltage as the supply voltage can be superimposed with AC voltage components. If such interference caused by ripple currents can be reliably identified, it is possible to eliminate or ignore such interference in the echo signals, so that the control unit does not identify any faulty objects. The interference can thus be overcome at low cost by improved signal processing of the received echo signals, which results in reliable detection of objects in the vicinity of the vehicle and, in particular, false positive detections of objects in the vicinity of vehicles are avoided. Such interference can be avoided or eliminated by means of circuitry solutions such as capacitors or else ripple filters as part of the provision of the common supply, for example in the control unit, which means that the interference can be dealt with cost-effectively. Compared to previous implementations, the sensors can also be used to transmit the sensor signals over a longer period of time, in particular in the form of a plurality of individual signal pulses that together form the respective sensor signal, as a result of which the sensors require more power, or they require the same power over a longer period of time , without having to amplify the supply via the control unit. Any faults that are to be expected over a longer period of time can be identified and overcome, so that objects in the area surrounding the vehicle can be detected without significant restrictions. Depending on the method of operating the sensor arrangement, the fault can be identified individually for a single group of sensors, ie without requiring knowledge of the operation of further groups of sensors. Alternatively, the interference is identified by timed operation of multiple groups of sensors as defined by the different group transmission phases.

A disturbance in the received echo signals of each group can be identified in different ways, which can be based on the transmitted sensor signals as well as on the received echo signals. It is therefore not necessary in both cases, directly at the source of the error, ie at the supply to be applied in order to identify the fault or to avoid it, the latter being associated with a great deal of effort.

On the one hand, the disturbance can be identified by comparing several of the received echo signals within a group. This usually relates to echo signals that are determined at the same time, in which disturbances in the common supply, which relates to the common supply of all sensors in the corresponding group, affect all sensors in the corresponding group due to disturbances in the reception of the echo signals. Depending on the configuration of the sensor arrangement with an arrangement of the sensors in a plurality of groups, the effects of supply errors can in principle also occur in the joint supply of several of the groups, depending on the operation and supply of the sensors in the different groups. In this case, in particular, the transmission of sensor signals with the sensors from other groups can disrupt the supply of sensors from another group or groups, so that the disruption is reflected in the received echo signals of the corresponding group. Disturbances in the supply of the sensors due to external influences, for example due to external interference signals that are unforeseeable and/or can occur randomly, as well as disturbances due to the operation of the supply of the sensors, for example in the control unit, can be identified. The interference in the received echo signals of the at least one group can be identified in fundamentally different ways based on a comparison of at least two of the received echo signals from the corresponding group. Details have already been set out above and are additionally given below. The interference can be detected, for example, based on simultaneous echoes in the echo signals and/or echoes with excessive amplitudes and/or echoes of the same type in the echo signals.

On the other hand, the fault can be identified by identifying a corresponding time window of this group transmission phase as a fault based on the group transmission phase of at least one other group. In this case, no further investigations or comparisons of the received echo signals are required, and the interference can be identified with little effort. Identifying the interference based on the offset in time and a duration of the group transmission phase of at least one other group can result in that Echo signals from the sensors of the group which receive echo signals during the group transmission phase of another group are identified as interference during that group transmission phase. As a result, real echoes from objects in the vehicle's surroundings can sometimes not be recognized and processed. However, various measures described below are possible in order to also be able to provide valid echo signals within this time window. In this case, the disturbances in the corresponding group usually occur for all the sensors included, since these sensors receive echo signals at the same time and are electrically supplied together. Correspondingly, disturbances in the common supply due to disturbances in the reception of the echo signals affect all sensors of the corresponding group, which are identified jointly based on the time offset of the group transmission phase and the duration of the group transmission phase. The group transmission phases are controlled by the control unit so that the fault can be easily identified directly in the control unit. The time offset relates, for example, to a start of the respective group transmission phases of the different groups. The time offset between the individual group transmission phases can be different, for example between different groups. The time offset can be chosen so that the group transmission phases of the different groups do not overlap. In this case, the group transmission phases are in each case pairwise disjoint time intervals. The duration of the individual group transmission phases can be different for different groups. In principle, the duration of the group transmission phases of the different groups in different cycles can also be different. The method is preferably carried out repetitively for the different groups. This can result in interference for each of the groups of sensors based on an activity, in particular the transmission of the sensor signals by the sensors of other groups. The time offset indicates a point in time from which interference can occur based on the joint supply of several groups of sensors, and together with the duration of the corresponding group transmission phase(s) a time interval is defined as interference.

The disturbances in the reception of the echo signals typically relate to errors in the internal signal processing, ie from a physical coupling of the echo signal into the respective sensor, if necessary, through to the generation of an envelope of the respective echo signal. Due to the propagation of the emitted sensor signals and the echo signals based thereon, it is often necessary to carry out signal processing, in particular signal amplification, of the physically coupled-in echo signal in order to reliably detect the reflections of the sensor signals as echo signals and to detect the echoes contained therein on the objects. For the detection of echo signals from reflection of the sensor signals on distant objects, an increasingly stronger electrical signal amplification, in particular signal amplification, of the received echo signals is required, which increases with the time after the transmission of the sensor signals, ie with a distance of the objects from the respective sensor. By identifying the disruptions, the sensors can thus also reliably detect objects at greater distances from the respective sensor. As a result, for example, incorrect emergency braking can be avoided by appropriate driving support systems.

The sensor arrangement is typically part of a driving assistance system of a vehicle or is connected to the driving assistance system in order to provide environmental information thereto in relation to objects in the vicinity of the vehicle. The driving support system can in principle be any driving support system with one or more support functions. Driving assistance systems of this type are known, for example, as driver assistance systems in order to support a human driver of the vehicle when driving the vehicle, for example as an emergency braking system, adaptive cruise control system, parking assistance system or others. However, such driving support systems can also provide functions that are used, for example, for autonomous or semi-autonomous driving of the vehicle.

The control unit is any computing unit that receives and processes the echo signals from the sensors. In the field of vehicles and driving support systems, such control units are known, for example, as ECUs (Electronic Control Units). In principle, other components can also be connected to the control unit. If these further components are connected to the common supply of the sensors and are supplied from there, as a result of which further potential sources of interference result from a supply of these further components through the common supply. The principles described here can be applied accordingly. The sensor arrangement comprises a plurality of sensors which are preferably designed in the same way for each group. For example, the sensors can be ultrasonic sensors or radar sensors, which emit corresponding ultrasonic signals or radar signals as sensor signals and receive echo signals of these sensor signals as ultrasonic echoes or radar echoes. In current vehicles, it is common that, for example, a first group of sensors is arranged along a front of the vehicle and a second group of sensors is arranged along a rear of the vehicle. Each group includes, for example, four to six individual sensors. In addition, groups of sensors can also be arranged along the longitudinal sides of the vehicles. The sensors are connected in parallel to the common supply, for example in the form of a supply line. Alternatively, the sensors of a group can be connected in the manner of a so-called daisy chain and in particular can be connected to the control unit.

The supply line can, for example, be laid parallel to one of the data lines and thus at the same time, so that both lines run together. Alternatively, only one line can be laid, which is used both as a supply line and as a data line, i.e. the sensors and the control unit communicate via the common line, and the control unit supplies the sensors via the common line. The supply line usually includes two potentials, typically a supply voltage and ground, which are provided via one or more individual electrical cables. Various bus systems are known as such, in which an integral design of supply line and data line is carried out, for example DSI3 or USV11.

The common supply causes electrical energy to be provided to all connected sensors. When supplied via the control unit, electrical energy is provided via the control unit. For this purpose, the control unit has, for example, an internal or an external supply circuit in order to provide electrical energy via the supply lines for all groups. In vehicles, a voltage adjustment can be made from an on-board voltage of the Vehicle of typically 12 volts to a desired supply voltage are carried out, in particular a voltage increase (boost).

The transmission of sensor signals takes place for each group in its respective group transmission phase, with these sensors in the group transmission phase typically emitting their sensor signals in a close time relationship, in particular simultaneously, in order to receive the respective echo signals simultaneously or in a close time relationship. The echo signals are based on reflections of the sensor signals on objects in the vicinity of the vehicle, so that distances to the objects can be determined from a time difference between the transmission of the sensor signals and the reception of echoes of the sensor signals on the objects. The echo signals thus indicate both a temporal definition of received echoes and a definition of a distance from objects belonging to the echoes.

Typically repetitive cycles are formed, in which the sensors of all groups transmit their sensor signals and receive the echo signals and transmit them to the control unit. Accordingly, the sensors can repeatedly emit sensor signals and receive the echo signals. If the sensor signals are sent out simultaneously or promptly within each group, a high repetition rate of the cycle can be achieved in order to continuously and promptly record the surroundings of the vehicle.

The transmission of the received echo signals from the sensors to the control unit takes place jointly, in particular within the respective cycle, it being possible, for example, for the echo signals to be transmitted from the individual sensors to the control unit with a time delay within one cycle. In principle, it is possible for the received echo signals to be transmitted from the sensors to the control unit in a cycle that follows the transmission of the sensor signals, in order to keep the cycles short. Correspondingly, echo signals of a current cycle can be received while the echo signal of the previous cycle is transmitted from the corresponding sensor to the control unit. In principle, the echo signals from one cycle can also be transmitted to the control unit in the cycle after the next or later. In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the transmission of sensor signals with the sensors, with the sensors of the at least one group transmitting their sensor signals in their respective group transmission phase, includes the transmission of at least two different sensor signals with the sensors of the at least one group, receiving echo signals based on reflections of the sensor signals includes receiving at least two different echo signals based on reflections of the at least two different sensor signals, and identifying a fault in the received echo signals of the at least one group takes place based on a comparison of at least two different types of received echo signals. The different types of sensor signals are emitted by sensors that are basically of the same type, but have at least one different feature, in particular with regard to a frequency of the sensor signal. For example, sensor signals with different ultrasonic frequencies can be used for the use of ultrasonic sensors. In this case, only one type of sensor signal can be transmitted by the sensors of the respective group, or at least some of the sensors of the corresponding group transmit the different types of sensor signals in regular or irregular sequences. Current ultrasonic sensors can be operated, for example, with different frequencies in a range from about 45kFlz to 60kFlz. In this case, interference from ripple currents in particular often has an uneven effect on the reception of the corresponding echo signals. Disturbances can thus be identified, for example, by the fact that they only occur for one frequency of the echo signals. The identification of the interference is therefore essentially based on different echoes in the at least two different types of echo signals. This applies in particular if the same echoes from real objects are to be expected for each of the different sensor signals based on a spatial proximity of the sensors which have received the different types of echo signals. A corresponding difference can also be identified when considering a plurality of the different types of echo signals in order to identify interference. The same applies to radar sensors.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors which are arranged in at least one group, this includes Transmission of at least two different sensor signals with the sensors of the at least one group, transmission of the at least two different sensor signals with different sensors of the at least one group. Different types of sensor signals can, for example, be emitted alternately by the ultrasonic sensors of the respective group according to their arrangement along the supply line. As a result, the environment can be reliably monitored based on the different types of echo signals if the echo signals can be assigned to the different types of sensor signals. Mutual influencing of the echo signals by the different types of sensor signals is reduced.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, receiving at least two different echo signals based on reflections of the at least two different sensor signals includes receiving the at least two different echo signals with at least one of the sensors the at least one group. When receiving different types of echo signals with a sensor, different sensor detections can be carried out for the location of the corresponding sensor. In this way it can be determined in a reliable manner whether the echo signal shows a disturbance or whether an echo contained therein belongs to a real object. The different types of sensor signals are typically transmitted using a plurality of sensors, in particular using adjacent sensors, in particular along a supply line. When receiving the different types of echo signals with a sensor, an echo that only occurs for one type of echo signal can be identified as a disturbance, since a real object should generate a corresponding echo for each of the different types of sensor signals for the location of the respective sensor.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, a fault in the received echo signals of a group is identified based on a comparison of at least two received echo signals from two different sensors of the at least one group , especially two sensors with a different arrangement. Disturbances in the common supply of a group affect all sensors contained in it equally, so that a disturbance in the supply becomes noticeable due to false echoes in all sensors in the group. The false echoes are very similar or even identical in terms of time and amplitude. The disturbance can therefore be recognized in the received echo signals of all sensors, it being possible, in principle, to consider only part of the received echo signals in order to recognize the disturbance. Preferably, the different arrangement of the sensors relates to an arrangement at the beginning and end of the corresponding group of sensors, ie those sensors which are farthest apart are considered to identify the disturbance, since in these sensors there is a probability of simultaneous echoes by real objects is particularly low. Accordingly, a fault can be identified particularly reliably.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the method includes masking an identified disturbance in the received echo signals of the at least one group, in particular in all received echo signals of the at least one group. The masking of the disturbance has the effect that false detections of objects in the area surrounding the vehicle can be reliably prevented. In this case it is sufficient if the interference is only identified in a part of the received echo signals in order to mask the interference in the received echo signals from all sensors of the corresponding group. The interference masking directly affects the echo signals transmitted to the control unit at the same time, i.e. in the same cycle. The receiving of the echo signals and the transmission of the received echo signals to the control unit can take place in different cycles.

In a further advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the masking of an identified interference in the received echo signals of the at least one group includes masking the identified interference when receiving further echo signals of the group . The additional echo signals are transmitted from the sensors to the control unit at a later point in time, for example in a subsequent cycle. The further echo signals therefore relate to echo signals received at a later point in time. In the case of regular faults, a masking of current Received echo signals carried out beyond masking, so for future cycles. The expression “when further echo signals are received” means that the interference in the currently received echo signals is not initially identified, but rather that the masking also takes place for the subsequently received echo signals of the group based on the previously identified interference. The masking preferably takes place in the control unit, it being possible for the masking to take place immediately upon receipt of the echo signals or at a later point in time during the processing of the echo signals.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the plurality of sensors of the sensor arrangement are arranged in at least two groups, with the sensors of each group transmitting their sensor signals in their respective group transmission phase, and the group transmission phases of the at least two groups have a time offset, and a disturbance in the received echo signals of the at least one group is identified based on a comparison of at least two received echo signals from the corresponding group, taking into account the time offset of the group transmission phases of other groups in each case. The time offset relates, for example, to a start of the respective group transmission phases of the different groups. The time offset between the individual group transmission phases can be different, for example for the different groups. In principle, the time offset in different cycles can also be different. The time offset can be chosen so that the group transmission phases of the different groups do not overlap. In this case, the group transmission phases are in each case pairwise disjoint time intervals. The duration of the individual group transmission phases can be different for different groups. In principle, the duration of the group transmission phases of the different groups in different cycles can also be different. The method is preferably carried out repetitively for the different groups. This can result in interference for each of the groups of sensors based on an activity, in particular the transmission of the sensor signals by the sensors of other groups. Disturbances in the received echo signals can also be identified for each of the groups of sensors. If the time offset is known, it is therefore possible to specifically search for interference in the received echo signals in order to identify them. The time offset indicates a point in time when to which disturbances can occur based on the common supply of several groups of sensors. Preferably, together with a known duration of the corresponding group transmission phase(s), a time interval is defined in which these disturbances can occur. To emit the signal pulses, the sensors typically require a particularly large amount of energy, with a large amount of electrical power having to be made available to a corresponding group in the short term when the signal pulses are emitted in the group transmission phase. As a result, interference in the received echo signals of the respective group can increasingly occur during the group transmission phase(s) of other groups. After the signal pulses have been emitted, the sensors receive the echo signals, for which purpose less electrical power usually has to be made available and the probability of interference occurring is reduced.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the method includes changing the time offset between the group transmission phases of the at least two groups between two cycles for transmitting the sensor signals of the corresponding group. Changing the time offset between the group transmission phases of the at least two groups has the effect that a time window in which the interference can occur is also shifted. As a result, for example, when masking the interference in the received echo signals, one area can be masked while another area is masked in a subsequent envelope. Correspondingly, with a suitable change in the time offset based on the two time-offset received echo signals, a complete detection of the surroundings can take place. Permanent masking of specific areas in the received echo signals can thus be avoided by changing the masking with the time offset. In particular when there is little dynamics in the area surrounding the vehicle, i.e. when objects in the area surrounding the vehicle move relatively slowly relative to the vehicle, the surroundings can be recorded very reliably and completely with the sensors despite the masking, even if they occur regularly disturbances.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors which are arranged in at least one group, this includes identifying a disturbance in the received echo signals of the at least one group based on a comparison of at least two of the received echo signals from the corresponding group identifying echoes in the received echo signals with the changed time offset over at least two cycles. Received echo signals from two or more cycles are therefore considered in order to identify interference. In this case, repetitive echoes from objects in the received echo signals which are essentially static with respect to the corresponding group transmission phases can indicate interference. In this way, recurring echoes can be reliably identified as disturbances, particularly in the case of high dynamics in the area surrounding the vehicle, ie when objects in the area surrounding the vehicle move quickly relative to the vehicle.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the transmission of sensor signals with the sensors of each group in their respective group transmission phase includes transmission of the sensor signals from the sensors of each group in at least two subgroups a time interval between the transmission of the sensor signals of the at least two subgroups, and the identification of a disturbance in the received echo signals of the at least one group based on a comparison of at least two of the received echo signals from the corresponding group comprises an identification of echoes in the at least two received echo signals with the time interval. The sensor signals are usually transmitted by the sensors of the at least two subgroups with a short time interval, so that the corresponding group transmission phase is as short as possible. The time interval is preferably of the order of magnitude of the duration of the transmission of the sensor signals. For example, the time interval can be a few milliseconds, for example three milliseconds or more, given an exemplary sensor signal with a duration of approximately 2.5 milliseconds. The at least two subgroups make it possible on the one hand to reduce the maximum power required for the corresponding group of sensors, thereby reducing the risk of ripple currents occurring. On the other hand, the transmission of the sensor signals in at least two subgroups with a time interval causes the disturbances caused thereby to have characteristic echoes in the received echo signals, which can be easily and reliably detected in order to identify them as disturbances. The time interval refers for example, to a start of transmission of the sensor signals of the subgroups. In principle, the transmission of the sensor signals of the sensors of the at least two subgroups can overlap in time. However, there is preferably no overlapping in order to avoid power peaks due to the overlapping transmission of the sensor signals with the sensors of the corresponding group. Inner and outer sensors preferably each form a subgroup, ie sensors at the beginning and at the end of the supply line, which are usually also positioned accordingly on the vehicle.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the identification of a disturbance in the received echo signals of the at least one group includes based on a comparison of at least two of the received echo signals from the corresponding group identifying echoes in the at least two received echo signals separated in time by at least two cycles. In this case, recurring, characteristic echoes from objects in the received echo signals can indicate a recurring fault, which can be identified particularly reliably, due to the transmission of the sensor signals in at least two subgroups at a time interval. Identifying the interference is made easier by the characteristic echoes in the received echo signals.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the sensor signals are emitted by the sensors of each group in at least two subgroups with a time interval between the emission of the sensor signals of the at least two subgroups Changing the time interval between two cycles for sending out the sensor signals of the corresponding group, and identifying a disturbance in the received echo signals of the at least one group based on a comparison of at least two of the received echo signals from the corresponding group includes identifying echoes in the received ones Echo signals with the changed time intervals over at least two cycles. A disturbance can be identified particularly reliably over at least two cycles by varying the time interval, since the disturbance will also change with the change in the time interval. a real one In contrast, the object will not change the shape of its echo in the received echo signals when the time interval changes, as a result of which a disturbance can be reliably identified. The disturbance can therefore be identified on the one hand by its shape and on the other hand by the change in accordance with the change in the time interval.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least one group, the receiving of echo signals based on reflections of the sensor signals includes receiving flow curves with the received echo signals, the transmission of the received echo signals from the sensors the control unit includes a transmission of the flow curves with the received echo signals, and the identification of a disturbance in the received echo signals of the at least one group is based on a comparison of at least two flow curves with the respectively received echo signals of the corresponding group. The received echo signals are thus completely transmitted with their flow curves from the sensors to the control unit. An envelope curve is generated in each case, for example beginning with the transmission of the sensor signal or after a predetermined time interval. The end of the envelope results from an end of a reception time for the reception of the reflections of the sensor signals. The envelope may be a continuous envelope or a discrete envelope having a plurality of discrete points which collectively define the envelope. For the transmission of the flow curves with the received echo signals, the above explanations with regard to the transmission of the received echo signals apply accordingly.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least two groups, the method includes changing the time offset between the group transmission phases of the at least two groups between two cycles for transmitting the sensor signals of the at least two groups. Changing the time offset between the group transmission phases of the at least two groups means that the interference also occurs at different times. As a result, for example, when masking the interference in the received echo signals, one area can be masked while another area is masked in a subsequent envelope. Accordingly, with a suitable change in the temporal offset based on the two temporally offset received echo signals, a complete detection of the environment. Permanent masking of specific areas in the received echo signals can thus be avoided by changing the masking with the time offset. In particular when there is little dynamics in the area surrounding the vehicle, ie when objects in the area surrounding the vehicle move only slowly relative to the vehicle, the surroundings can be recorded very reliably and completely with the sensors despite the masking, even if they occur regularly disturbances.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors, which are arranged in at least two groups, includes identifying a disturbance in the received echo signals of each group based on the time offset of the group transmission phases and a duration of the group transmission phases of other groups identifying the interference in the received echo signals of each group based on a comparison of at least two of the received echo signals of the corresponding group. The time offset and the duration of the group transmission phases therefore specify a time window or time interval in which the interference is identified based on the comparison of the at least two of the received echo signals of the corresponding group. This enables faults to be precisely identified by first restricting the occurrence of the faults by the time window and then specifically identifying faults in this time window. Areas outside of this time window do not have to be checked for faults, which means that the method can also be carried out very efficiently. With regard to the echo signals, reference is made to the above statements relating to the method for operating a sensor arrangement having a plurality of sensors arranged in at least one group.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least two groups, the identification of the interference in the received echo signals of each group based on a comparison of at least two of the received echo signals of the corresponding group includes an identification of echoes in the received echo signals of each group with the changed time offset over at least two cycles. It So received echo signals from two or more cycles are considered to identify interference. In this case, repetitive echoes from objects in the received echo signals which are essentially static with respect to the corresponding group transmission phases can indicate interference. In this way, recurring echoes, ie essentially static echoes, can be reliably identified as disturbances, particularly when there is high dynamics in the area surrounding the vehicle, ie when objects in the area surrounding the vehicle move quickly relative to the vehicle.

In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least two groups, the method includes masking an identified disturbance in the received echo signals of the at least two groups, in particular in all received echo signals of the at least two groups. The masking of the disturbance has the effect that false detections of objects in the area surrounding the vehicle can be reliably prevented. The masking of the interference directly relates to the echo signals transmitted to the control unit at the same time, ie in the same cycle. The receiving of the echo signals and the transmission of the received echo signals to the control unit can take place in different cycles. In addition, masking an identified interference in the received echo signals of the at least one group can include masking the identified interference when receiving further echo signals of the group. The additional echo signals are transmitted from the sensors to the control unit at a later point in time, for example in a subsequent cycle. The further echo signals therefore relate to echo signals received at a later point in time. In the case of regular disturbances, masking that goes beyond masking currently received echo signals can also take place, ie for future cycles. The expression “when further echo signals are received” means that the interference in the respectively currently received echo signals is not initially identified, but rather that masking also takes place for the subsequently received echo signals of the group based on the previously identified interference. The masking preferably takes place in the control unit, it being possible for the masking to take place immediately upon receipt of the echo signals or at a later point in time during the processing of the echo signals. In an advantageous embodiment of the method for operating a sensor arrangement with a plurality of sensors arranged in at least two groups, receiving echo signals based on reflections of the sensor signals includes receiving envelopes with the received echo signals and transmitting the received echo signals from the sensors to the control unit includes transmitting the envelopes with the received echo signals. The received echo signals are thus completely transmitted with their envelopes from the sensors to the control unit. An envelope curve is generated in each case, for example beginning with the transmission of the sensor signal or after a predetermined time interval. The end of the envelope results from an end of a reception time for the reception of the reflections of the sensor signals. The envelope may be a continuous envelope or a discrete envelope having a plurality of discrete points which collectively define the envelope. For the transmission of the envelope curves with the received echo signals, the above explanations with regard to the transmission of the received echo signals apply accordingly.

The invention is explained in more detail below with reference to the attached drawing based on preferred embodiments. The features shown can represent an aspect of the invention both individually and in combination. Features of different exemplary embodiments can be transferred from one exemplary embodiment to another.

It shows

1 shows a schematic view of a vehicle with a driving assistance system with a sensor arrangement according to a first preferred embodiment,

2 shows a schematic representation of part of the sensor arrangement from FIG. 1 with a control unit and a group of sensors which are connected to one another via a supply line,

3 shows an exemplary representation of an envelope curve of an echo signal which is transmitted from one of the sensors of the sensor arrangement to the control unit via the supply line, without interference, 4 shows an exemplary representation of an envelope curve of an echo signal, which is transmitted from one of the sensors of the sensor arrangement to the control unit via the supply line, with a disturbance,

Fig. 5 shows a flow chart of a method of a first embodiment for

operation of the sensor arrangement of the first embodiment, and

Fig. 6 is a flow chart of a method of a third embodiment for

Operation of the sensor arrangement of the first or second embodiment.

FIG. 1 shows a vehicle 10 with a driving support system according to a first preferred embodiment.

The driving support system can in principle be any driving support system with one or more support functions. The driving assistance system can be designed as a driver assistance system to support a human driver of the vehicle 10 in driving the vehicle 10, for example as an emergency braking system, adaptive cruise control system, parking assistance system or others. Alternatively or additionally, the driving support system can provide functions that are used for autonomous or partially autonomous driving of the vehicle 10 .

The driving support system has a sensor arrangement 12 . The sensor arrangement 12 comprises a control unit 14 and a plurality of sensors 16.

The control unit 14 is an arbitrary computing unit. In the field of vehicles 10 and driving support systems, such control units 14 are known, for example, as ECUs (Electronic Control Units).

The plurality of sensors 16 are arranged in two groups 18, 20 on the vehicle 10. In this exemplary embodiment, the sensors 16 are designed as ultrasonic sensors 16 . All sensors 16 are designed here in the same way. A first group 18 of sensors 16 is arranged along a front of the vehicle 10 and a second group 20 of sensors 16 is arranged along a rear of the vehicle 10 . Each of the two groups 18, 20 is shown in FIG. 1 as an example shown with five individual sensors 16. Sensors 16 monitor surroundings 22 of vehicle 10 by detecting objects in surroundings 22 of vehicle 10 .

The sensors 16 of each of the two groups 18, 20 are connected in parallel to a supply line 24, which is formed by two individual lines 26, 28 in each case. Each of the two groups 18 , 20 with sensors 16 is connected to the control unit 14 via its own supply line 24 . The sensors 16 of both groups 18, 20 receive a common electrical supply from the control unit 14 via the corresponding supply lines 24.

The supply line 24 is used here at the same time as a data line 30, i.e. the sensors 16 and the control unit 14 communicate via the supply line 24. Various bus systems are known as such, in which an integral design of supply line 24 and data line 30 is carried out, for example DSI3 or UPS11 . The sensor arrangement 12 is shown in detail in FIG. 2 with the supply line 24 and data line 30 . An alternative embodiment of the supply line 24 with the data line 30 is also possible.

The control unit 14 is connected to a battery 32 of the vehicle 10, from which it receives electrical energy for supplying the sensors 16 of the two groups 18, 20 via the corresponding supply lines 24.

A method, shown in FIG. 5, for operating the sensor arrangement 12 of the first specific embodiment is explained below. Some of the steps specified in the described method can be changed in their order or are also optional, as is evident to the person skilled in the art.

The method begins with step S100, which relates to the transmission of sensor signals with the sensors 16. The ultrasonic sensors 16 emit ultrasonic pulses or ultrasonic pulse sequences as sensor signals. The ultrasonic sensors 16 of each group 18, 20 transmit their sensor signals simultaneously in a common group transmission phase. The ultrasonic sensors 16 of each group 18, 20 emit two different types of sensor signals, namely ultrasonic signals with one high ultrasonic frequency and ultrasonic signals with a low ultrasonic frequency in a frequency range for ultrasonic signals from about 45kHz to 60kHz.

The ultrasonic sensors 16 of the respective group 18, 20 emit the two different sensor signals alternately according to their arrangement along the supply line 24.

Step S110 relates to receiving echo signals based on reflections of the sensor signals. The echo signals are received based on reflections of the sensor signals that were transmitted in step S100. Correspondingly, the ultrasonic sensors 16 of each of the groups 18, 20 receive two different types of echo signals based on the reflections of the two different types of sensor signals. Each of the ultrasonic sensors 16 simultaneously receives echo signals for both ultrasonic frequencies of the transmitted ultrasonic signals, i.e. each ultrasonic sensor 16 receives on two frequency channels.

In the present case, envelopes 34, 36 with the received echo signals are received with the ultrasonic sensors 16. Corresponding envelope curves 34, 36 are shown in FIGS. 3 and 4 by way of example.

The reflections of the sensor signals occur on objects in the surroundings 22 of the vehicle 10, so that distances to the objects can be determined in the control unit 14 from a time difference between the transmission of the sensor signals and the reception of the echo signals.

Step S120 relates to a transmission of the envelopes 34, 36 with the received echo signals from the sensors 16 to the control unit 14. In this exemplary embodiment, each envelope 34, 36 comprises, by way of example, a complete period of time from the transmission of the sensor signal to the end of a reception time for the reception of the Reflections of the sensor signals. The envelope 34,36 may be a continuous or a discrete envelope 34,36 having a plurality of discrete points which collectively define the envelope 34,36. The transmission of the envelopes 34, 36 with the echo signals received from the sensors 16 to the control unit 14 takes place together, with a time-delayed transmission of the envelopes 34, 36 from the individual sensors 16 taking place. In addition, the envelopes 34, 36 of the Sensors 16 are transmitted to the control unit 14 in a cycle following the transmission of the sensor signals.

Step S130 relates to identifying a disturbance 38 in the envelopes 34, 36 of the received echo signals of each group 18, 20 based on a comparison of the envelopes 34, 36 of the received echo signals from the corresponding group 18, 20.

First, the interference 38 in the envelopes 34, 36 of the received echo signals of a group 18, 20 is identified based on a comparison of the envelopes 34, 36 from a plurality of sensors 16 in the group 18, 20 for the same frequency channel in each case. As can be seen from FIG. 3, the envelope curve 34 there has no disturbance 38 . The envelope 34 of Figure 3 contains multiple echoes 40 from objects in the area 22 of the vehicle 10.

In contrast, the envelope curve 36 of Figure 4 shows, in addition to the echoes 40, which are also shown in Figure 3, an interference 38 which is shown in a similar way in the envelope curves 34, 36 of all sensors 16 for the same frequency channel, i.e. the interference 38 is similar or even identical in terms of time or distance and amplitude in the considered envelopes 34, 36 for the corresponding frequency channel. If the disturbance 38 is therefore visible for the same frequency channel for all sensors 16, the disturbance 38 is recognized as such.

In addition, a fault 38 is identified by comparing the respective two envelope curves 34, 36 based on the two different types of echo signals for each of the ultrasonic sensors 16, ie the envelope curves 34, 36 of the two received frequency channels are compared for each of the sensors 16 with one another. The interference 38 can - for example depending on the type of interference 38 - only be visible in one of the frequency channels, i.e. the envelope curve 34, 36 of a frequency channel is, as shown in Figure 3, without any discernible interference 38, and the envelope curve 34, 36 of the another frequency channel has a recognizable interference 38, as shown in FIG. The interference 38 is identified in that one frequency channel shows the interference 38 and the other frequency channel does not. Step S140 relates to masking of the identified interference 38 in all envelopes 34, 36 of the received echo signals of each of the groups 18, 20. Thereby the interference 38 in the envelopes 34, 36 is masked out so that no false positive detections of objects in the environment 22 of the vehicle 10 take place. Depending on the type of interference 38, the masking can affect the envelopes 34, 36 of only one frequency channel or of both frequency channels.

In this exemplary embodiment, the method is carried out repeatedly in cycles, with a cycle for the sensors 16 comprising steps S100 to S120. In general terms, the repetitive method also includes steps S130 and S140.

The second embodiment, which is based on the sensor arrangement 12 and the method of the first embodiment, is described below. Accordingly, differences between the two embodiments will be described. In case of doubt, features of the second embodiment that are not described in detail correspond to those of the first embodiment.

The method of the second embodiment is carried out using the sensor arrangement 12 of the second embodiment, the sensor arrangement 12 of the second embodiment having the same structure as the sensor arrangement 12 of the first embodiment.

Deviating from the method of the first embodiment, in step S100 sensor signals are sent with the sensors 16, with the sensors 16 of each group 18, 20 sending out their sensor signals at the same time in their respective group sending phase, and with the group sending phases of the two groups 18, 20 having a time have an offset. The time offset is chosen so that the group transmission phases of the different groups 18, 20 do not overlap. In this case, the group transmission phases are disjoint time intervals.

Deviating from the method of the first embodiment, in step S130 a disturbance 38 is identified in the envelopes 34, 36 of the received echo signals of a respective group 18, 20, taking into account the time offset of the group transmission phases. Based on the known time offset together with the duration of the corresponding group transmission phase(s), which is also known, there is a time interval in which disturbances 38 can occur in the supply, namely disturbances caused by the transmission of the echo signals of the other group 18, 20. Therefore, a disturbance 38 is identified in the envelopes 34, 36 of the received echo signals of a group 18, 20 for precisely these time ranges. There is a time interval in which these disturbances 38 can occur. In this time interval, based on the supply by the control unit 14 during the transmission of the sensor signals, the disturbances 38 are specifically searched for in the envelopes 34, 36 in order to identify them easily.

In this exemplary embodiment, too, the method is carried out repeatedly in cycles, with a cycle for the sensors 16 comprising steps S100 to S120. The cycles of the two groups 18, 20 are offset from one another by the time offset.

A method shown in FIG. 6 according to a third specific embodiment for operating the sensor arrangement 12 of the first specific embodiment is explained below. Some of the steps specified in the described method can be changed in their order or are also optional, as is evident to the person skilled in the art. In principle, the method can also be carried out correspondingly with the sensor arrangement 12 of the second embodiment.

The method of the third embodiment corresponds in part to the method of the first embodiment. Accordingly, differences between the two embodiments will be described. In case of doubt, features of the third embodiment that are not described in detail correspond to those of the first embodiment.

The method begins with step S200, which relates to a transmission of sensor signals with the sensors 16. Step S200 essentially corresponds to step S100 of the method of the first specific embodiment.

Step S210 relates to receiving echo signals based on reflections of the sensor signals. Step S210 corresponds to step S110 of the method of the first embodiment. Step S220 relates to transmitting the envelopes 34, 36 with the received echo signals from the sensors 16 to the control unit 14. Step S220 corresponds to step S120 of the method of the first embodiment.

Step S230 relates to identifying a disturbance 38 in the received envelopes 34, 36 of each group 18, 20 based on the temporal offset of the group transmission phase and a duration of the group transmission phase of at least one other group 18, 20. The group transmission phase of the first group 18 is classified as disturbance in the envelopes 34, 36 of the sensors 16 of the second group 20, and the group transmit phase of the second group 20 is identified as interference in the envelopes 34, 36 of the sensors 16 of the first group 18. The fault is identified for all sensors 16 of the corresponding group 18, 20.

Step S240 relates to masking of the identified interference 38 in all envelopes 34, 36 of the received echo signals of each of the groups 18, 20. Step S240 corresponds to step S140 of the method of the first embodiment.

Step S250 relates to changing the time offset between the group transmission phases of the two groups 18, 20 between two cycles for transmitting the sensor signals of the two groups 18, 20.

The method of the third specific embodiment is repeated here in cycles, with a cycle for the sensors 16 comprising the steps S200 to S220. In general terms, the repetitive method also includes steps S230 to S250.

Reference List

10 vehicle

12 sensor arrangement

14 control unit

16 sensor, ultrasonic sensor

18 first group

20 second group

22 environment

24 supply line

26 line

28 line

30 data line

32 battery

34 envelope without interference, channel 1

36 envelope with noise, channel 2

38 disturbance

40 Echoes

Claims

patent claims

Claims 1. A method for operating a sensor arrangement (12) having a control unit (14) and a plurality of sensors (16) which are arranged in at least one group (18, 20), the sensors (16) being connected to a common electrical supply , in particular via the control unit (14), comprising the steps

Transmission of sensor signals with the sensors (16), the sensors (16) of each group (18, 20) transmitting their sensor signals in their respective group transmission phase,

receiving echo signals based on reflections of the sensor signals,

transmitting the received echo signals from the sensors (16) to the control unit (14), and

identifying a disturbance (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two of the received echo signals from the corresponding group (18, 20).

2. The method according to claim 1, characterized in that the transmission of sensor signals with the sensors (16), the sensors (16) of the at least one group (18, 20) transmitting their sensor signals in their respective group transmission phase, an transmission of at least two different types of sensor signals with the sensors (16) of the at least one group (18, 20), the receiving of echo signals based on reflections of the sensor signals includes receiving at least two different types of echo signals based on reflections of the at least two different types of sensor signals, and identifying a fault (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two different types of received echo signals.

3. The method according to claim 2, characterized in that the sending of at least two different sensor signals with the sensors (16) of the at least one group (18, 20) means sending the at least two different sensor signals with different sensors (16) of the at least one group (18, 20).

4. The method according to any one of claims 2 or 3, characterized in that the receiving of at least two different types of echo signals based on reflections of the at least two different types of sensor signals receiving the at least two different types of echo signals with at least one of the sensors (16) of the at least one group ( 18, 20).

5. The method according to any one of the preceding claims, characterized in that the identification of a disturbance (38) in the received echo signals of a group (18, 20) based on a comparison of at least two received echo signals from two different sensors (16) of the at least one Group (18, 20) takes place, in particular of two sensors (16) with a different arrangement.

6. The method according to any one of the preceding claims, characterized in that the method comprises masking an identified disturbance (38) in the received echo signals of the at least one group (18, 20), in particular in all received echo signals of the at least one group (18 , 20).

7. The method according to any one of the preceding claims, characterized in that the plurality of sensors (16) of the sensor arrangement (12) are arranged in at least two groups (18, 20), the sensors (16) of each group (18, 20) in their respective group transmission phase send out their sensor signals, and the Group transmission phases of the at least two groups (18, 20) have a time offset, and identifying interference (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two of the received echo signals from the corresponding group (18, 20) taking into account the time offset of the group transmission phases of other groups (18, 20).

8. Method according to the preceding claim 7, characterized in that the method comprises changing the time offset between the group transmission phases of the at least two groups (18, 20) between two cycles for transmitting the sensor signals of the corresponding group (18, 20).

9. The method according to the preceding claim 8, characterized in that the identification of a disturbance (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two of the received echo signals from the corresponding group (18, 20) identifying echoes in the received echo signals with the changed time offset over at least two cycles.

10. Method according to one of the preceding claims, characterized in that the transmission of sensor signals with the sensors (16) of each group (18, 20) in their respective group transmission phase involves transmission of the sensor signals from the sensors (16) of each group (18, 20 ) in at least two subgroups with a time interval between the transmission of the sensor signals of the at least two subgroups, and the identification of a disturbance (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two of the received ones echo signals from the corresponding group (18, 20) comprises identifying echoes in the at least two received echo signals with the time interval.

11 . Method according to the preceding claim 10, characterized in that identifying a disturbance (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two of the received echo signals from the corresponding group (18, 20) identifying echoes in the at least two received echo signals with the time spacing over at least two cycles.

12. The method according to the preceding claim 11, characterized in that the transmission of the sensor signals from the sensors (16) of each group (18, 20) in at least two subgroups with a time interval between the transmission of the sensor signals of the at least two subgroups causes a change in the time interval between two cycles for sending out the sensor signals of the corresponding group (18, 20), and identifying a disturbance (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two of the received echo signals from the corresponding group (18, 20) identifying echoes in the received echo signals with the changed time intervals over at least two cycles.

13. The method according to any one of the preceding claims, characterized in that receiving echo signals based on reflections of the sensor signals includes receiving envelopes (34, 36) with the received echo signals, transmitting the received echo signals from the sensors (16) to the Control unit (14) includes transmitting the envelopes (34, 36) with the received echo signals, and identifying a disturbance (38) in the received echo signals of the at least one group (18, 20) based on a comparison of at least two envelopes (34 , 36) with the respectively received echo signals of the corresponding group (18, 20).

14. A method for operating a sensor arrangement (12) with a control unit (14) and a plurality of sensors (16) which are arranged in at least two groups (18, 20), the sensors (16) being connected to a common electrical supply , in particular via the control unit (14), comprising the steps

Transmission of sensor signals with the sensors (16), the sensors (16) of each group (18, 20) transmitting their sensor signals in their respective group transmission phase, and the group transmission phases of the at least two groups (18, 20) having a time offset,

receiving echo signals based on reflections of the sensor signals,

identifying a disturbance (38) in the received echo signals of each group (18, 20) based on the time offset of the group transmission phase and a duration of the group transmission phase of at least one other group (18, 20).

15. The method according to the preceding claim 14, characterized in that the method comprises changing the time offset between the group transmission phases of the at least two groups (18, 20) between two cycles for transmitting the sensor signals of the at least two groups (18, 20).

16. The method according to any one of the preceding claims 14 or 15, characterized in that the identification of a disturbance (38) in the received echo signals of each group (18, 20) based on the time offset of the group transmission phases and a duration of the group transmission phases of other groups (18, 20) identifying the interference (38) in the received echo signals of each group (18, 20) based on a comparison of at least two of the received echo signals of the corresponding group (18, 20).

17. Method according to the preceding claim 16 in combination with claim 15, characterized in that the identification of the interference (38) in the received echo signals of each group (18, 20) is based on a comparison of at least two of the received echo signals of the corresponding group ( 18, 20) identifying echoes in the received echo signals of each group (18, 20) with the changed time offset over at least two cycles.

18. The method according to any one of the preceding claims, characterized in that the method comprises masking an identified interference (38) in the received echo signals of the at least two groups (18, 20), in particular in all received echo signals of the at least two groups (18 , 20).

19. The method according to any one of the preceding claims 14 to 18, characterized in that receiving echo signals based on reflections of the sensor signals includes receiving envelopes (34, 36) with the received echo signals, and transmitting the received echo signals from the sensors ( 16) comprises transmitting the envelope curves (34, 36) with the received echo signals to the control unit (14).

20. Sensor arrangement (12) for a vehicle (10) with a control unit (14), and a plurality of sensors (16) in at least one group (18, 20) are arranged, wherein the sensors (16) to a common electrical Supply are connected, in particular via the control unit (14), characterized in that the sensor arrangement (12) is designed to operate according to the method according to any one of the preceding claims 1 to 13.

21 . Sensor arrangement (12) for a vehicle (10) with a control unit (14) and a plurality of sensors (16) arranged in at least two groups (18, 20), the sensors (16) being connected to a common electrical supply are, in particular via the control unit (14), characterized in that the sensor arrangement (12) is designed for operation according to the method according to one of the preceding claims 14 to 19.

22. Driving support system for a vehicle (10) with a sensor arrangement (12) according to one of the preceding claims 20 or 21.